Stored energy operating device



April 8, 1958 J. A. FAVRE 2,829,737

STORED ENERGY OPERATING DEVICE Filed Feb. 14, 1957 2 Sheets-Sheet 1Inventor:

John A. Fa: re, bg v His A carnag- April 8, 1958 J. A. FAVRE 2,829,737

STORED ENERGY OPERATING DEVICE Filed Feb. 14, 1957 2 Sheets-Sheet 2Inventor:

ttorney.

2,829,737 STORED ENERGY OPERATING DEVICE John A. Favre, Broomall, Pa.,assignor to General Electric Company, a corporation of New YorkApplication February 14, 1957, Serial No. 640,178

10 Claims. (Cl. 185-'37) This invention relates to a stored-energyoperating device and, more particularly, to a stored-energy operatingdevice which is especially suited for high-speed closing and reclosingof large electric circuit breakers.

The invention is more specifically concerned with improvements in thegeneral type of stored-energy device disclosed and claimed in my PatentNo. 2,674,345, assigned to the assignee of the present invention. Theoperating device disclosed in the aforementioned patent comprises aheavy compression spring which is charged by the action of a smallelectric motor rotating 2. spring- States Patent controlling membertoward a dead-center position with respect to the spring. Rotation ofthe controlling memt and this discharging action is utilized to produceclosing of a circuit breaker.

A disadvantage of the patented device is that, if by chance, thespring-controlling member should be stopped short of its latchedposition and within the angle of repose in the region of dead-center,then subsequent re lease of the latching means would have no effect onthe spring. The spring would be stalled due to its inability in thisposition to overcome the opposing forces of static friction. As aresult, the spring would be ineffective to produce closing of thecircuit-breaker in the desired manner, at least until otherwisedischarged.

Another disadvantage of the patented device is that it relies for itssuccessful operation upon the latched or blocked position of thecontrolling member being located beyond the angle of repose for theoperator. Otherwise, the above-described stalling of the spring wouldtake place upon release of the latch means. The problem which resultsfrom locating the latched position beyond the angle of repose is that insuch location the heavy spring, which is then fully charged, is exertinga large force on thelatch means. This not only severely stresses thestructural parts of the latch means but also necessitates the use ofrelatively large forces in order to subsequently release the latchmeans.

Accordingly, an object of my invention is to provide a stored-enrgyoperator of this general type in which release of the latch meansconsistently produces immediate spring discharge, even in those caseswhere the springcontrolling member had been stopped short of its latchedor blocked position and within the angle of repose of the operator.

Another object is to construct the operator in such a manner that itispossible to locate the above-described overcenter latching positionwithin the angle of repose.

Another object is to construct the stored-energy device in such a mannerthat the latch which restrains the spring in charged position can bereleased by a force of relativity low magnitude.

In carrying out my invention in one form, I charge a main spring bydriving a rotatable spring-controlling 2,829,737 Patented Apr. 8, 8

spring. Rotation of the spring-controlling member is continued until itis carried past geometric dead-center. Upon movement of thespring-controlling member into a predetermined position past deadcenter, the spring acts to discharge and thereby to further rotate thespring-controlling member. Such further rotation is blocked, however, bya stopmember which is held in a blocking position by suitable releasablelatch means. Release of the latch means renders the stop memberinefiective to block said further rotation and also brings intooperation an auxiliary spring. This auxiliary spring. acts through thestop memher to drive the spring-controlling member through aidpredetermined position past dead-center, whereupon the main spring thenacts-to discharge and further rotate the spring-controlling member.

For a betterunderstanding of my invention, reference may be had to thefollowing specification taken in connection with the accompanyingdrawings, wherein:

Fig. 1 is a diagrammatic representation of a circuitthereof being shownin the same operative positions as shown in Fig. 1.

Fig. 3 is an enlarged side-elevational view of the operating device withthe parts thereof shown in operative positions differentfrom those ofFig. 2.

Referring now to Fig. 1,the stored-energy operator is shown at It andthe circuit-breaker which it is designed to close is shown at 12. Thiscircuit breaker 12 can be of any suitable conventional type and is,accordingly, shown in schematic form only.

As shown in Fig. l, the circuit breaker 12 comprises a pair ofrelatively-movable interrupting contacts 18 and 19. One of thesecontacts 18 is pivotally mounted at 18a and is biased to theopen-circuit position shown by a suitable spring 20. Closing forces aretransmitted to the movable contact 18 by a conventional trip-freeoperating mechanism which comprises a pair of toggle links 21 and 22pivotally joined together by a knee 23. One of the toggle links 21 ispivotally connected at its opposite end to movable contac'tlb, whereasthe other of the toggle links 22 is connected by a pivot pin 22a to theupper end of a guide link 24. This guide link 24 is pivotally supportedat its lower end on a fixed fulcrum 26. The pivot pin 22a carries alatch roller 23 which cooperates with a suitable trip latch 30. So longas the trip latch 30 remains in the latched position shown, the toggle21, 22 is capable of transmitting thrust to the movable contact 18.Thus, when the knee 23 is lifted from the position 1 Fig. l,it lifts theknee and produces closing in the manner I described hereinabove.Preferably, the cam 35 is arranged to drive the toggle 21, 22 slightlyovercenter and against a stop 37 so that the movable contact will beheld in closed-circuit position even when the cam 35 is returned to itsoriginal position of Fig. 1.

Should the latch 30 be tripped when the breaker is closed, or evenduring the closing stroke, the toggle 21, 22 will be renderedinoperative to transmit thrustto the movable contact 18. As a result,the opening spring 20 will be free to drive the movable contact 18 toits opencircuit position. A suitable resetting spring 38 cooperates withthe guide link 24 to reset the mechanism to the described tripping ofthe latch 30 is accomplished in response to predetermined electricalconditions by relying upon a suitable solenoid 32.

For driving the cam 35 counterclockwise to produce the above-describedclosing of the circuit-breaker 12, the stored-energy operating device isrelied upon. Referring to Figs. 1 and 2, this operating device 10comprises a pivotally-mounted lever 40 which is keyed to a drive shaft41. The drive shaft 41 is rotatably mounted in conventional bearings andis suitably coupled to thecam 35. Thus, when the lever 48 is drivencounterclockwise from its position of Fig. l or Fig. 2, it acts throughthe cam 35 to produce circuit-breaker closing.

For imparting such counterclockwise closing motion to the lever 40, aheavy compression spring 42 is provided. This compression spring 42reacts at its lower end against a stationary abutment 43 and at itsupper end against an adapter 44 which is pivotally coupled to the lever40 through a transverse pin 45 carried by the lever 40. The compressionspring 42 is releasably held in a charged posi ti-on, which is shown inFig. l, by means of a rotatable spring-controlling crank 47 coactingwith a cam surface 48 formed at the outer end of the pivotal lever 40.The controlling'crank 47 is mounted for overcenter action with respectto the compression spring 42, and when the crank 47 releases the lever40 (in a manner soon to be described), the compression spring 42 quicklydischarges and drives the lever 40 counterclockwise to close thebreaker.

Referring to Figs. 1 and 2, the spring-controlling crank 47 is keyed toa rotatable shaft 50 and comprises a transversely projecting crank pin51 located at its outer end. Carried on the crank pin 51 is anantifriction roller 52 which is freely rotatable thereon but is suitablyrestrained against axial movement thereon. One portion of this roller 52engages the cam surface 48 of the lever 40, whereas another portion isdisposed to engage a projecting portion 54a of a stop member 54. As willsoonv appear more clearly, the stop member 54 is releasably latched inthe position of Fig. 2 and is operable, so long as held in thisposition, to block clockwise motion of the crank 47 beyond the positionof Fig. 2.

In the position of Figs. 1 and 2, the crank 47 is located beyonddead-center with respect to the line of action of the compression spring42, but only slightly therebeyond, and

preferably still'within the angle of repose. By the term angle of reposeis meant that angular distance in the region of geometric dead-centerwithin which the spring,

42 provides insufficient rotational force component to overcome theopposing static friction. Assuming then that the crank 47, as shown inFigs. 1 and 2, is within the angle of repose, it would be necessary in.order to initiate. discharge of the spring 42 to further rotate the Forrotating the crank 47 clockwise through'this outer limit of the angle ofrepose, I provide an auxiliary, or kick-off, spring 56, which is coupledto one end of the stop member 54. This auxiliary spring 56 is acompression spring tending to rotate the stop member 54 counterclockwiseabout its supporting pivot 58. The auxiliary spring is normallyrestrained from so rotating the stop member 54 by releasable latchingmeans 60 (soon to be described). When, however, thelatching means, 60 isreleased, the auxiliary spring 56 responds by rapidlydriving the stopmember 54 in a counterclockwise direction. .A

cam surface 59 formed on the upper portion of the stop member 54transmits this motion to the crank pin 51 with sufiicient impact topromptly drive the crank 47 clockwise-beyond the angle. of repose,whereuponthe main spring 42 quickly discharges. In this chain of events,

the projecting portion 54a of the stop member 54 offered no oppositionto such discharge inasmuch as it had been rotated out of the path of thecrank pin roller 52 by the auxiliary spring 56. Because of its actionduring the above-described starting operation, the member 54 willoccasionally be referred to hereinafter as a starter member. It will beapparent that the starting forces transmitted through this member 54from the auxiliary spring 56 act through a line of action which isangularly spaced from the line of action of the main spring 42.

The latching means 69 comprises a prop 61 against which the lower end ofthe stop member 54 abuts. The prop 61 is rotatable about a pivot 62 butis held in an elevated, undercenter position by a latching cam 63 seatedbeneath the prop 61. When the latching cam 63 is pivoted in acounterclockwise direction about the axis of its mounting shaft 64, itmoves out of supporting relationship with the prop 61. As soon as thisoccurs, the stop member 54 becomes free to rotate in a counterclockwisedirection brushing aside the prop 61. This allows the auxiliary spring56 to discharge and produce the operations described above. A lighttension spring 61a biasing the prop 61 toward its position of Figs. 1and 2 is utilized to aid in subsequent resetting of the latch means 60.

For pivoting the latching cam 63 counterclockwise so as to effect theabove-described release of the latching means 60, a solenoid 65 isprovided. When this solenoid 65 is energized, it drives its armature 66downwardly. This produces counterclockwise rotation of a lever 66a,which is keyed to the shaft 64, and thereby produces the desiredcounterclockwise movement of the latching cam 63, which is also keyed tothe shaft 64. A suitable resetting spring 67 is coupled to the latchingcam 63 for resetting the latching cam to its position of Figs. 1 and 2at an appropriate instant after the solenoid 65 is subsequentlydeenergized.

Release of the latching means 69 can also be effected manually. To thisend, a manually operable lever 68 pivoted at 68a is provided. When thislever is pivoted in a clockwise direction, it acts against a pin 69,carried by the latching cam 63, to produce counterclockwise trippingmovement of the latching cam 63.

After the main spring 42 has discharged to produce the above-describedclosing of the circuit breaker 12, the spring is recharged by means of asuitable unidirectional motor 70. This motor 70 is connected to thecrank 47 through a slip clutch 72, reduction gears 74, and theoverrunning clutch 76. These latter components may be of any suitableconventional type and are, therefore, shown in schematic form only.Preferably, however, they correspond'to similar components depicted inmy U. S. Patents 2,674,345 and 2,667,076, which are assigned to theassignee of the present invention. The primary purpose of theoverrunning clutch 76 is to assure that the desired high-speed dischargeof the main spring 42 will not be impeded by the inertia of thereduction gears 74 or the armature of motor 70. To this end, theoverrunning clutch 76 permits the main spring 42, in discharging, todrive the crank 47 clockwise independently of the reduction gears 74 andthe motor armature. As shown in my aforesaid patents, suitable pawl andratchet means are associated with the reduction gears 74 to insureagainst back-tracking of the crank 47.

For energizing the motor 70 to initiate recharging action, anormally-open switch '78 connected in series with the motor is provided.The movable contacts of this switch 78 are preferably actuated by acontrol rod 79 connected to the stop member 54 and, accordingly, theyare closed assoon as the stop member 54 initiates dischargeof the mainspring 42. The motor 70 thereupon begins to operate but does-notovertake the crank 47 until the crank has decelerated near the endof theclosing stroke. When this occurs, the'motor acts to continuegitheclockwiserotation of the crank 47 and thereby to recharge thethen-discharged main spring 42, as will soon be described. Fig. 4 showsthe position of the crank 47 as this recharging action is beginning.

Considering now a spring-charging operation-when the crank 47 is drivenclockwise by the motor 70 from the position of Fig. 3, it acts throughthe roller 52 and the cam surface 48 to force the lever 40 downwardly,thereby compressing the main spring 42. As this action progresses andthe crank 47 approaches a lower dead-center position with respect to themain spring 42, the roller 52 on the crank pin 51 engages a followersurface 54b formed on the stop member 54. Thereafter, continuedclockwise movement of the crank 47 drives the stop member 54 clockwiseabout its pivot 58, thus compressing the auxiliary spring 56 and, ineffect, resetting the stop member 54 toward its initial position ofFig. 1. After a predetermined amount of such clockwise resettingmovement of the stop member 54, the latching mechanism 60 is free toreset underneath the stop member 54. Thereafter, continued clockwisemovement of the crank 47 carries the roller 52 off of the followersurface 54b, and the latching mechanism 60 acts through the stop member54 to hold the auxiliary spring 56 charged. The position of the stopmember 54 when it has been latched in place by the latching mechanism 60is shown in Figs. 1 and 2.

The above-described chargingoperation is terminated by opening theenergizing circuit for the motor 70 at an instant which is appropriatefor assuring latching of the stop member 54. To this end, the switchcontrol rod 79 opens the motor-controlling contacts 78 when the stopmember 54 nears the end of its clockwise movement. Thereafter, the crank47 coasts into its final position shown in Figs. 1 and 2.

This final position, as previously indicated, is beyond geometricdead-center relative to the main spring 42, but only slightly therebeyond and preferably within the angle of repose. As a result, thestatic friction which-is present is alone sufiicient to hold the mainspring in the charged position of Figs. 1 and 2. Accordingly, the mainspring 42 is then exerting no material force upon the stop member 54 orupon the latching mechanism 60. This is highly desirable not onlybecause of the low stresses imposed upon the latching mechanism 60 butalso because it enables me to utilize a relatively small solenoid (65)for subsequently releasing the stop member 54. The main spring 42, ineffect, produces no frictional forces which oppose the subsequentlatch-releasing action of the solenoid 65. l

The primary purpose of the projection 54a formed on the stop member 54is to assure that the crank 47 is not unintentionally driven clockwisepast the position of Figs. 1 and 2. For example, if the crank 47 coastedexcessively after motor cut-off, or, if for any reason, the motorcut-otf switch 78 failed to open in the desired manner, the projection54a would block movement of the crank 47 past the position of Figs. 1and 2. The slip clutch 72, which is'connected between the motor 70 andthe gear train 74, assures that excessive forces are not transmittedfrom the motor to the stop member 54 when the crank engages the stopmember. slip clutch slips, or yields, in a well-known manner when theforces being transmitted therethrough reach a predetermined maximum safelevel.

After the operating device has been driven into the position of Figs. 1and 2, closing of the circuit-breaker can again be initiated in the samemanner as previously described. That is, the latching mechanism 60 canbe released by the solenoid to allow the auxiliary spring 56 to drivethe stop member 54 into engagement with roller 52. This quickly carriesthe crank 47 through the outer limit of the angle of repose, at whichtime the main spring 42 is free to discharge and produce breakerclosing.

An important advantage of my disclosed operating device 10 resides inthe fact that the main spring can be suc- To this end, the

cessfully discharged even if the crank 47 ,had been previously stoppedshort of the position of Figs. 1 and 2. In this regard, so' lOng as thecrank roller 52 had been stopped at any point between the projection 54aand the surface 54b of the stop member, the main spring can still besuccessfully discharged. This follows from the fact that theauxiliary-spring 56 is capable of driving the crank 47 through theangle'of repose irrespective of the precise initial position of thecrank roller 52, provided, of course, that this initial position isclockwise beyond the surface 54b of the stop member 54.

In vew of this relatively wide range of acceptable initial positions, itwill be apparent that the motor cut-off point during a chargingoperation is not highly critical. Minor variations can be tolerated inthe point at which such cutofi occurs without materially afliecting asubsequent discharging operation.

Proper electrical control of the spring-releasing solenoid 65 isobtained by relying upon a suitable XY control scheme. This controlscheme, which is shown diagrammatically in Fig. 1, comprises aclosing-control switch connected in series with the coil of solenoid 65across a suitable source of control power. This switch 85 may beoperated either manually or by suitable condition-responsive means. Alsoconnected in series with the coil of solenoid 65 are the normally-closedcontacts 86a of an anti-pump relay 86 and the contacts 87 of a breakerauxiliary switch. This auxiliary switch is a so-called b switch, thatis, its contacts 87 are closed when the circuit breaker 12 is open andare open when the circuit breaker 12 is closed.

Assume first that the breaker l2 and its operating device 10 are in theposition of Fig. 1 and that it is desired to close the breaker. Theclosing-control switch S5 is first operated to closed position, and thisestablishes an energizing circuit for the solenoid 65' which extendsfrom one terminal of the power source, through the contacts 86a, 87, andthe coil of solenoid 65, to the other terminal. Upon. energization, thesolenoid 6S releases the latch means 60 and allows the auxiliary spring56 to actuate the stop member 54 to initiate breaker-closing dischargeof the main spring 42. Such actuation of the stop member 54 closes anormally-open cut-oif switch 90 coupled to the stop member, and thisresults in the establishment of an energizing circuit for the anti-pumprelay 86. The relay 86 responds by opening its normally closed contacts86a and closing its normally-open contacts 86b. Closing of the contacts.86b establishes a seal-in circuit for the antipump relay 86, which holdsthis relay 86 in its operated position so long as the closing controlswitch S5 is held closed. This seal-in circuit extends from the plusterminal, through the switch 85, the contacts 86b, and the coil of theanti-pump relay 86 to the other terminal.

When the motor '70 completes its charging operation (in the mannerpreviously described), the cut-off switch 90 returns to its openposition of Fig. 1. If, at this time, the attendant should still beholding the closing control switch 85 closed, the aforementioned seal-incircuit through the contacts 8612 will be maintaining the antipump relay86 energized. So long as the relay 86 remains energized in this mannerits contacts 86a remain open thereby preventing another operation frombeing initiatedby the closing-control switch 85 so long as such switchis held closed. It is necessary to first reopen the closing-controlswitch 35 before another breaker-closing operation can be initiated.Thus, pumping is effectively prevented.

As pointed out hereinabove, I prefer to locate the normal blockedposition of the spring-controlling crank 47 within the angle of reposeso as to reduce the loading on the latching mechanism (60) and so as toenable the latch to be released by a relatively small solenoid. If thesefactors are not controlling, then the normal blocked position can belocated slightly beyond the outer limit of is unintentionally stoppedslightly shortof its normal I blocked position and within the angle ofrepose, the starter means 54, 56 will act to initiate spring dischargeupon release of the latching means 60, thereby assuring against stallingof the spring.

In those applications in which it is desired to effect automaticreelosing of the above-described circuit breaker, the closing controlswitch 85 is arranged to close automatically in response to abreaker-opening operation, thereby initiating an automatic reclosure.Circuits for providing the desired control over the closing-controlswitch 8d are well-known, and reference may be had to Stewart Patent1,943,096, assigned to the assignee of this application, for an exampleof such a circuit.

It may be desirable in certain of these reclosing appli cations to delaythe automatic reclosing operation until.

a predetermined interval of time has elapsed after circuit-breakeropening. Such a delay can be provided in this general type of operatingdevice by utilizing the motor 70, instead of the auxiliary spring 56,for initially driving the spring-controlling crank 47. In such amodified arrangement, the initial position of the spring-controllingcrank 47 would be within the angle of repose Additionally, in thismodified arrangement, theauxiliary spring 56 would be of such a sizethat it would provide insufiicient force to drive the spring-controllingcrank 47, but would merely have sufficient power to drive the unlatchedstop member 54 into engagement with the, spring-.

controlling crank 47. Such movement of the stop member 54 would move theprojection 54a out of blocking position with respect ot thespring-controlling crank 47 and would also close the motor-energizingswitch 73. Upon energization, the motor 70 would drive thespringcontrolling crank 47 through the outer limit of the angle ofrepose, whereupon the main spring 42 would discharge to producecircuit-breaker closing.

This modified arrangement produces a delay in reclosing which isdependent upon the speed at which the motor drives the crank 47 and uponthe distance which the crank is initially spaced from the outer limit ofthe angle of repose. By a suitable choice of these two quantities, adesired delay in reclosing can be obtained.

While I have shown and described particular embodiments of my invention,it will be obvious to those skilled.

in the art that various changes and modifications may be made withoutdeparting from my invention in its broader aspects and I, therefore,intend in the appended claims to cover all such changes andmodifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patents of theUnited States is:

l. in a stored-energy operating device, a main spring, rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead-centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring-controller in response torotative movement of said springcontroller into a predetermined positionpast said dead-.

center position, a movable stop member coacting with member is providedwith means forming a follower surface through which charging forces aretransmitted from said spring-controller to said auxiliary spring uponmovementof said spring-controller adjacent said dead-center position,said latch means acting until released to hold said auxiliary springcharged.

3. In a stored-energy operating device, a main spring,

a rotatable spring-controller mounted for over-center,

action with respect to said main spring, means for transmitting chargingforces to said main spring in response to rotation of saidspring-controller toward a dead-center position with respect to saidspring, said spring acting to discharge and thereby further rotate saidspringcontroller in response to rotative movement of saidspring-controller into a predetermined position past said dead-centerposition, a movable stop member coacting with said spring-controller,releasable latch means for holding said stop member in a position forblocking said further rotation of the spring-controller, release of saidlatch means rendering said stop member ineffective to block said furtherrotation, and auxiliary spring means acting through a line of actionwhich is angularly spaced from that of said main spring for drivingsaidrotatable spring-controller through said predetermined position pastdead-center position in response to release of said latch means.

4. In a stored energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead-centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring controller in response torotative movement of said spring controller into a predeterminedposition past said dead center position, a pivoted stmter membercoacting with said spring controller, auxiliary spring means biasingsaid starter member into a position wherein said starter member isadapted to receive resetting forces from said springcontroller duringmovement of said springcontroller adjacent said dead center position,said starter member being provided with follower means through whichsaid resetting forces act to pivot said starter member in a direction tocharge said auxiliary spring means, latch means operable after apredetermined charging of said auxiliary spring means for holding saidstarter member in a position wherein said auxiliary spring means ischarged, stop means for blocking movement of said spring controllerthrough said predetermined position past said dead center position, saidauxiliary spring acting in response to release of said latching means toimpart through said starter member forces which drive said.

spring controller through said predetermined position past dead center,and operation-initiating means for releasing said latching means and forrendering said stop means ineffective to block said spring controller.

5. in a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead-centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said springcontroller in response to rotativemovement of said spring-controller through the outer limit of the angleof response in the region of said dead-center position, a movable stopmember coacting with said spring-controller, releasable latch means forholding said stop member in a position for blocking movement of saidspring;

controller beyond said angle of repose, release of said latch meansrendering said stop member ineffective to block said spring-controller,auxiliary spring means acting through said stop member upon release ofsaid latch means for driving said spring-controller through the outerlimit of said angle of repose whereupon said main spring then acts todischarge and further rotate said springcontroller.

6. In a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead-centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring-controller in response torotative movement of said spring-controller through the outer limit ofthe angle of repose in the region of said dead-center position, amovable stop member coacting with said spring-controller, releasablelatch means for holding said stop member in a position for blockingmovement of said spring-controller beyond said angle of repose, releaseof said latch means rendering said stop member ineffective to block saidspring-controller, and auxiliary spring means acting through a differentline of action than said main spring for driving said spring-controllerthrough the outer limit of said angle of repose in response to releaseof said latch means.

7. in a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring-controller in response torotative movement of said spring controller through the outer limit ofthe angle of repose in the region of said dead center position, stopmeans arranged to block movement of said spring-controller before thespring-controller moves through the outer limit of the angle of repose,thus holding said spring in a charged condition, discharge-initiatingmeans operable to render said stop means inefiective to block saidspring-controller, and means for driving said spring-controller throughthe outer limit of said angle of repose upon operation of saiddischarge-initiating means.

8. In a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means including a motor for driving said rotatablespring-controller, means for transmitting charging forces to said mainspring in response to rotation of said spring-controller toward a deadcenter position with respect to said spring, said spring acting todischarge and thereby further rotate said spring controller in responseto rotative movement of said springcontroller through the outer limit ofthe angle of repose in the region of said dead center position, stopmeans arranged to block movement of said spring-controller 10 before thespring-controller moves through the outer limit of the angle of reposethus holding said spring in a charged condition, discharge-initiatingmeans operable to render said stop means ineffective to block saidspringcontroller, and means for causing said motor to drive saidspring-controller through the outer limit of said angle of repose uponoperation of said discharge-initiating means.

9. In a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action With respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring-controller in response torotative movement of said spring controller through the outer limit ofthe angle of repose in the region or" said dead center position, stopmeans arranged to block movement of said spring-controller before thespring-controller moves through the Outer limit of the angle of reposethus holding said spring in a charged condition, discharge-initiatingmeans operable to render said stop means ineifective to block saidspring-controller, and auxiliary spring means acting through a difierentline of action than said main spring for driving said springcontrollerthrough the outer limit of said angle of repose upon operation of saiddischarge-initiating means.

10. In a stored-energy operating device, a main spring, a rotatablespring-controller mounted for over-center action with respect to saidmain spring, means for transmitting charging forces to said main springin response to rotation of said spring-controller toward a dead-centerposition with respect to said spring, said spring acting to dischargeand thereby further rotate said spring-com troller in response torotative movement of said springcontroller into a predetermined positionpast said deadcenter position, stop means arranged to block said furtherrotation of the spring-controller, thus holding said spring in a chargedcondition, discharge-initiating means operable to render said stop meansineffective to block said spring-controller, and auxiliary spring meansacting in response to operation of said discharge-initiating means todrive said spring-controller through said predetermined position pastdead-center whereupon said main spring then acts to discharge andfurther rotate said spring-controller, said auxiliary spring meansacting through a different line of action than said main spring.

References Cited in the file of this patent UNITED STATES PATENTS

